From: Fred Lindberg
Date: June 28 1999 7:40pm
Subject: Re: to much fragmentation
List-Archive: http://lists.mysql.com/mysql/6081
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On Mon, 28 Jun 1999 10:40:05 -0700, Scott Hess wrote:
>What we've found to happen is that all of your clients are hitting the
>database, and at some point it catastrophically degrades - performance
>doesn't plateau (sp?), it degrades. Our best simulations indicate that this
>point is where the number of transactions per second to the disk drive
>passes a certain point (this is as opposed to megabytes per second). At
This is a problem of your OS. Modern OS's, e.g. linux, will use unused
memory as cache. Performance will degrade when you don't have memory to
hold the blobs. In this case, you don't have memory to hold the blob
table and thus access to the db would require disk access. At that
point it depends on which system is better at caching the blobs.
(AFAIK)
-Sincerely, Fred
(Frederik Lindberg, Infectious Diseases, WashU, St. Louis, MO, USA)